package cn.cy.util;


import org.apache.log4j.Logger;
import org.apache.struts2.util.StrutsTypeConverter;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.*;

/**
 * date工具类
 * 框架类型转换
 */
public class DateUtil extends StrutsTypeConverter  {
    private  static final Logger log  = Logger.getLogger(DateUtil.class);
    private final DateFormat[] dfs = {
            //new SimpleDateFormat("yyyy年MM月dd日"),
            new SimpleDateFormat("yyyy-MM-dd"),
            //new SimpleDateFormat("yyyy/MM/dd"),
    };
    @Override
    public Object convertFromString(Map map, String[] strings, Class aClass) {
        log.info("进入类型转换- - - - - - convertFromString ");
        String dateStr = strings[0];
        log.info("参数- - - - - - "+dateStr);
        for(int i = 0 ; i < dfs.length ; i++){
            try{
                return dfs[i].parse(dateStr);
            }catch (Exception ex ){
                log.error(ex);
                continue;
            }
        }
        throw  new RuntimeException("ERROR");
    }

    @Override
    public String convertToString(Map map, Object o) {
        Date date = (Date)o;
        log.info("进入类型转换- - - - - - convertToString");
        return new SimpleDateFormat("yyyy-MM-dd").format(date);
    }

    // 用来全局控制 上一周，本周，下一周的周数变化
    private int weeks = 0;
    private int MaxDate;// 一月最大天数
    private int MaxYear;// 一年最大天数
    private static Calendar calendar = Calendar.getInstance();//实例化日历

    public DateUtil(){
        this.MaxYear = 365;
        this.MaxDate = 30;
    }

    public DateUtil(int MaxYear , int MaxDate ){
        this.MaxYear = MaxYear;
        this.MaxDate = MaxDate;
    }
    /**测试
     * @param args
     */
    public void main1(String[] args) {
        DateUtil tt = new DateUtil();
        System.out.println("获取当天日期:" + tt.getNowTime("yyyy-MM-dd"));
        System.out.println("获取本周一日期:" + tt.getMondayOFWeek());
        System.out.println("获取本周日的日期~:" + tt.getCurrentWeekday());
        System.out.println("获取上周一日期:" + tt.getPreviousWeekday());
        System.out.println("获取上周日日期:" + tt.getPreviousWeekSunday());
        System.out.println("获取下周一日期:" + tt.getNextMonday());
        System.out.println("获取下周日日期:" + tt.getNextSunday());
        System.out.println("获得相应周的周六的日期:" + tt.getNowTime("yyyy-MM-dd"));
        System.out.println("获取本月第一天日期:" + tt.getFirstDayOfMonth());
        System.out.println("获取本月最后一天日期:" + tt.getDefaultDay());
        System.out.println("获取上月第一天日期:" + tt.getPreviousMonthFirst());
        System.out.println("获取上月最后一天的日期:" + tt.getPreviousMonthEnd());
        System.out.println("获取下月第一天日期:" + tt.getNextMonthFirst());
        System.out.println("获取下月最后一天日期:" + tt.getNextMonthEnd());
        System.out.println("获取本年的第一天日期:" + tt.getCurrentYearFirst());
        System.out.println("获取本年最后一天日期:" + tt.getCurrentYearEnd());
        System.out.println("获取去年的第一天日期:" + tt.getPreviousYearFirst());
        System.out.println("获取去年的最后一天日期:" + tt.getPreviousYearEnd());
        System.out.println("获取明年第一天日期:" + tt.getNextYearFirst());
        System.out.println("获取明年最后一天日期:" + tt.getNextYearEnd());
        System.out.println("获取本季度第一天:" + tt.getThisSeasonFirstTime(11));
        System.out.println("获取本季度最后一天:" + tt.getThisSeasonFinallyTime(11));
        System.out.println("---------------->");
        System.out.println("获取当前月的第几周：" + tt.getWeekOfMonth());
        System.out.println("获取当前年份：" + tt.getYear());
        System.out.println("获取当前月份：" + tt.getMonth());
        System.out.println("获取今天在本年的第几天：" + tt.getDayOfYear());

        System.out.println("获得今天在本月的第几天(获得当前日)：" + tt.getDayOfMonth());
        System.out.println("获得今天在本周的第几天：" + tt.getDayOfWeek());
        System.out.println("获得半年后的日期：" + tt.convertDateToString(tt.getTimeYearNext()));
    }

    /**
     * 获得当前年份
     *
     * @return
     */
    public static int getYear() {
        return calendar.get(Calendar.YEAR);
    }

    /**
     * 获得当前月份
     *
     * @return
     */
    public static int getMonth() {
        return calendar.get(Calendar.MONTH) + 1;
    }

    /**
     * 获得今天在本年的第几天
     *
     * @return
     */
    public static int getDayOfYear() {
        return calendar.get(Calendar.DAY_OF_YEAR);
    }

    /**
     * 获得今天在本月的第几天(获得当前日)
     *
     * @return
     */
    public static int getDayOfMonth() {
        return calendar.get(Calendar.DAY_OF_MONTH);
    }

    /**
     * 获得今天在本周的第几天
     *
     * @return
     */
    public static int getDayOfWeek() {
        return calendar.get(Calendar.DAY_OF_WEEK);
    }

    /**
     * 获得今天是这个月的第几周
     *
     * @return
     */
    public static int getWeekOfMonth() {
        return calendar.get(Calendar.DAY_OF_WEEK_IN_MONTH);
    }

    /**
     * 获得半年后的日期
     *
     * @return
     */
    public static Date getTimeYearNext() {
        calendar.add(Calendar.DAY_OF_YEAR, 183);
        return calendar.getTime();
    }

    public static String convertDateToString(Date dateTime){
        SimpleDateFormat df=new SimpleDateFormat("yyyy-MM-dd");
        return df.format(dateTime);
    }

    /**
     * 得到二个日期间的间隔天数
     */
    public static String getTwoDay(String sj1, String sj2) {
        SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
        long day = 0;
        try {
            java.util.Date date = myFormatter.parse(sj1);
            java.util.Date mydate = myFormatter.parse(sj2);
            day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
        } catch (Exception e) {
            return "";
        }
        return day + "";
    }

    /**
     * 根据一个日期，返回是星期几的字符串
     *
     * @param sdate
     * @return
     */
    public static String getWeek(String sdate) {
        // 再转换为时间
        Date date = DateUtil.strToDate(sdate);
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        // int hour=c.get(Calendar.DAY_OF_WEEK);
        // hour中存的就是星期几了，其范围 1~7
        // 1=星期日 7=星期六，其他类推
        return new SimpleDateFormat("EEEE").format(c.getTime());
    }

    /**
     * 将短时间格式字符串转换为时间 yyyy-MM-dd
     *
     * @param strDate
     * @return
     */
    public static Date strToDate(String strDate) {
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
        ParsePosition pos = new ParsePosition(0);
        Date strtodate = formatter.parse(strDate, pos);
        return strtodate;
    }

    /**
     * 两个时间之间的天数
     *
     * @param date1
     * @param date2
     * @return
     */
    public static long getDays(String date1, String date2) {
        if (date1 == null || date1.equals(""))
            return 0;
        if (date2 == null || date2.equals(""))
            return 0;
        // 转换为标准时间
        SimpleDateFormat myFormatter = new SimpleDateFormat("yyyy-MM-dd");
        java.util.Date date = null;
        java.util.Date mydate = null;
        try {
            date = myFormatter.parse(date1);
            mydate = myFormatter.parse(date2);
        } catch (Exception e) {
        }
        long day = (date.getTime() - mydate.getTime()) / (24 * 60 * 60 * 1000);
        return day;
    }

    // 计算当月最后一天,返回字符串
    public String getDefaultDay() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.set(Calendar.DATE, 1);// 设为当前月的1号
        lastDate.add(Calendar.MONTH, 1);// 加一个月，变为下月的1号
        lastDate.add(Calendar.DATE, -1);// 减去一天，变为当月最后一天

        str = sdf.format(lastDate.getTime());
        return str;
    }

    // 上月第一天
    public String getPreviousMonthFirst() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.set(Calendar.DATE, 1);// 设为当前月的1号
        lastDate.add(Calendar.MONTH, -1);// 减一个月，变为下月的1号
        // lastDate.add(Calendar.DATE,-1);//减去一天，变为当月最后一天

        str = sdf.format(lastDate.getTime());
        return str;
    }

    // 获取当月第一天
    public String getFirstDayOfMonth() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.set(Calendar.DATE, 1);// 设为当前月的1号
        str = sdf.format(lastDate.getTime());
        return str;
    }

    // 获得本周星期日的日期
    public String getCurrentWeekday() {
        weeks = 0;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 6);
        Date monday = currentDate.getTime();

        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    // 获取当天时间
    public String getNowTime(String dateformat) {
        Date now = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat(dateformat);// 可以方便地修改日期格式
        String hehe = dateFormat.format(now);
        return hehe;
    }

    // 获得当前日期与本周日相差的天数
    private int getMondayPlus() {
        Calendar cd = Calendar.getInstance();
        // 获得今天是一周的第几天，星期日是第一天，星期二是第二天......
        int dayOfWeek = cd.get(Calendar.DAY_OF_WEEK) - 1; // 因为按中国礼拜一作为第一天所以这里减1
        if (dayOfWeek == 1) {
            return 0;
        } else {
            return 1 - dayOfWeek;
        }
    }

    // 获得本周一的日期
    public String getMondayOFWeek() {
        weeks = 0;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus);
        Date monday = currentDate.getTime();

        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    // 获得相应周的周六的日期
    public String getSaturday() {
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks + 6);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    // 获得上周星期日的日期
    public String getPreviousWeekSunday() {
        weeks = 0;
        weeks--;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + weeks);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    // 获得上周星期一的日期
    public String getPreviousWeekday() {
        weeks--;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 * weeks);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    // 获得下周星期一的日期
    public String getNextMonday() {
        weeks++;
        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    // 获得下周星期日的日期
    public String getNextSunday() {

        int mondayPlus = this.getMondayPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, mondayPlus + 7 + 6);
        Date monday = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preMonday = df.format(monday);
        return preMonday;
    }

    private int getMonthPlus() {
        Calendar cd = Calendar.getInstance();
        int monthOfNumber = cd.get(Calendar.DAY_OF_MONTH);
        cd.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        cd.roll(Calendar.DATE, -1);// 日期回滚一天，也就是最后一天
        MaxDate = cd.get(Calendar.DATE);
        if (monthOfNumber == 1) {
            return -MaxDate;
        } else {
            return 1 - monthOfNumber;
        }
    }

    // 获得上月最后一天的日期
    public String getPreviousMonthEnd() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.MONTH, -1);// 减一个月
        lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        lastDate.roll(Calendar.DATE, -1);// 日期回滚一天，也就是本月最后一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    // 获得下个月第一天的日期
    public String getNextMonthFirst() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.MONTH, 1);// 减一个月
        lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    // 获得下个月最后一天的日期
    public String getNextMonthEnd() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.MONTH, 1);// 加一个月
        lastDate.set(Calendar.DATE, 1);// 把日期设置为当月第一天
        lastDate.roll(Calendar.DATE, -1);// 日期回滚一天，也就是本月最后一天
        str = sdf.format(lastDate.getTime());
        return str;
    }

    // 获得明年最后一天的日期
    public String getNextYearEnd() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.YEAR, 1);// 加一个年
        lastDate.set(Calendar.DAY_OF_YEAR, 1);
        lastDate.roll(Calendar.DAY_OF_YEAR, -1);
        str = sdf.format(lastDate.getTime());
        return str;
    }

    // 获得明年第一天的日期
    public String getNextYearFirst() {
        String str = "";
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        Calendar lastDate = Calendar.getInstance();
        lastDate.add(Calendar.YEAR, 1);// 加一个年
        lastDate.set(Calendar.DAY_OF_YEAR, 1);
        str = sdf.format(lastDate.getTime());
        return str;

    }

    // 获得本年有多少天
    private int getMaxYear() {
        Calendar cd = Calendar.getInstance();
        cd.set(Calendar.DAY_OF_YEAR, 1);// 把日期设为当年第一天
        cd.roll(Calendar.DAY_OF_YEAR, -1);// 把日期回滚一天。
        int MaxYear = cd.get(Calendar.DAY_OF_YEAR);
        return MaxYear;
    }

    private int getYearPlus() {
        Calendar cd = Calendar.getInstance();
        int yearOfNumber = cd.get(Calendar.DAY_OF_YEAR);// 获得当天是一年中的第几天
        cd.set(Calendar.DAY_OF_YEAR, 1);// 把日期设为当年第一天
        cd.roll(Calendar.DAY_OF_YEAR, -1);// 把日期回滚一天。
        int MaxYear = cd.get(Calendar.DAY_OF_YEAR);
        if (yearOfNumber == 1) {
            return -MaxYear;
        } else {
            return 1 - yearOfNumber;
        }
    }

    // 获得本年第一天的日期
    public String getCurrentYearFirst() {
        int yearPlus = this.getYearPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, yearPlus);
        Date yearDay = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preYearDay = df.format(yearDay);
        return preYearDay;
    }

    // 获得本年最后一天的日期 *
    public String getCurrentYearEnd() {
        Date date = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
        String years = dateFormat.format(date);
        return years + "-12-31";
    }

    // 获得上年第一天的日期 *
    public String getPreviousYearFirst() {
        Date date = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
        String years = dateFormat.format(date);
        int years_value = Integer.parseInt(years);
        years_value--;
        return years_value + "-1-1";
    }

    // 获得上年最后一天的日期
    public String getPreviousYearEnd() {
        weeks--;
        int yearPlus = this.getYearPlus();
        GregorianCalendar currentDate = new GregorianCalendar();
        currentDate.add(GregorianCalendar.DATE, yearPlus + MaxYear * weeks
                + (MaxYear - 1));
        Date yearDay = currentDate.getTime();
        DateFormat df = DateFormat.getDateInstance();
        String preYearDay = df.format(yearDay);
        return preYearDay;
    }

    // 获得本季度第一天
    public String getThisSeasonFirstTime(int month) {
        int array[][] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 }, { 10, 11, 12 } };
        int season = 1;
        if (month >= 1 && month <= 3) {
            season = 1;
        }
        if (month >= 4 && month <= 6) {
            season = 2;
        }
        if (month >= 7 && month <= 9) {
            season = 3;
        }
        if (month >= 10 && month <= 12) {
            season = 4;
        }
        int start_month = array[season - 1][0];
        int end_month = array[season - 1][2];

        Date date = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
        String years = dateFormat.format(date);
        int years_value = Integer.parseInt(years);

        int start_days = 1;// years+"-"+String.valueOf(start_month)+"-1";//getLastDayOfMonth(years_value,start_month);
        int end_days = getLastDayOfMonth(years_value, end_month);
        String seasonDate = years_value + "-" + start_month + "-" + start_days;
        return seasonDate;

    }

    // 获得本季度最后一天
    public String getThisSeasonFinallyTime(int month) {
        int array[][] = { { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 }, { 10, 11, 12 } };
        int season = 1;
        if (month >= 1 && month <= 3) {
            season = 1;
        }
        if (month >= 4 && month <= 6) {
            season = 2;
        }
        if (month >= 7 && month <= 9) {
            season = 3;
        }
        if (month >= 10 && month <= 12) {
            season = 4;
        }
        int start_month = array[season - 1][0];
        int end_month = array[season - 1][2];

        Date date = new Date();
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");// 可以方便地修改日期格式
        String years = dateFormat.format(date);
        int years_value = Integer.parseInt(years);

        int start_days = 1;// years+"-"+String.valueOf(start_month)+"-1";//getLastDayOfMonth(years_value,start_month);
        int end_days = getLastDayOfMonth(years_value, end_month);
        String seasonDate = years_value + "-" + end_month + "-" + end_days;
        return seasonDate;

    }

    /**
     * 获取某年某月的最后一天
     *
     * @param year
     *            年
     * @param month
     *            月
     * @return 最后一天
     */
    private int getLastDayOfMonth(int year, int month) {
//            if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8
//                    || month == 10 || month == 12) {
//                return 31;
//            }
//            if (month == 4 || month == 6 || month == 9 || month == 11) {
//                return 30;
//            }
//            if (month == 2) {
//                if (isLeapYear(year)) {
//                    return 29;
//                } else {
//                    return 28;
//                }
//            }
        return 0;
    }

    /***
     *
     *获取所在月的第一天日期
     * */
    public static String getFirstDayOfMonth(String date) {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        try {

            calendar.setTime(sdf.parse(date));
            calendar.set(Calendar.DATE, 1);

        } catch (ParseException e) {

            e.printStackTrace();
        }

        return sdf.format(calendar.getTime());
    }

    /***
     * 获取所在月的最后一天时间
     *
     * */
    public static String getLastDayOfMonth(String date) {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        try {

            calendar.setTime(sdf.parse(date));
            calendar.set(Calendar.DATE, 1);// 设为当前月的1号
            calendar.add(Calendar.MONTH, 1);// 加一个月，变为下月的1号
            calendar.add(Calendar.DATE, -1);// 减去一天，变为当月最后一天

        } catch (ParseException e) {

            e.printStackTrace();
        }

        return sdf.format(calendar.getTime());
    }

    /***
     *
     * 上月第一天
     *
     * */
    public static String getPreviousMonthFirst(String date) {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        try {

            calendar.setTime(sdf.parse(date));
            calendar.set(Calendar.DATE, 1);// 设为当前月的1号
            calendar.add(Calendar.MONTH, -1);// 减一个月，变为下月的1号

        } catch (ParseException e) {

            e.printStackTrace();
        }

        return sdf.format(calendar.getTime());
    }

    /***
     *
     * 上月最后一天
     *
     * */
    public static String getPreviousMonthEnd(String date) {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        try {

            calendar.setTime(sdf.parse(date));
            calendar.add(Calendar.MONTH, -1);// 减一个月
            calendar.set(Calendar.DATE, 1);// 把日期设置为当月第一天
            calendar.roll(Calendar.DATE, -1);// 日期回滚一天，也就是本月最后一天

        } catch (ParseException e) {

            e.printStackTrace();
        }

        return sdf.format(calendar.getTime());
    }


    /***
     * 获取所在年的第一天
     *
     * **/
    public static String getFirstDayOfYear(String date) {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        try {

            calendar.setTime(sdf.parse(date));
            calendar.set(Calendar.DAY_OF_YEAR, 1);


        } catch (ParseException e) {

            e.printStackTrace();
        }

        return sdf.format(calendar.getTime());
    }

    /**
     *
     * 当前时间去年的日期
     * */
    public static String getDayOfLastYear(String date) {

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        try {

            calendar.setTime(sdf.parse(date));
            calendar.add(Calendar.YEAR, -1);

        } catch (ParseException e) {

            e.printStackTrace();
        }

        return sdf.format(calendar.getTime());
    }

    /****
     *
     * 系统当前时间
     * */
    public static String getCurrentDate (){

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        return sdf.format(calendar.getTime());
    }

    /**
     * 得到几天前的时间
     * @param d
     * @param day
     * @return
     */
    public static Date getDateBefore(Date d,int day){
        Calendar now =Calendar.getInstance();
        now.setTime(d);
        now.set(Calendar.DATE,now.get(Calendar.DATE)-day);
        return now.getTime();
    }

    /**
     * 得到几天后的时间
     * @param d
     * @param day
     * @return
     */
    public static Date getDateAfter(Date d,int day){
        Calendar now =Calendar.getInstance();
        now.setTime(d);
        now.set(Calendar.DATE,now.get(Calendar.DATE)+day);
        return now.getTime();
    }


    /****
     *
     *
     * 计算月份差
     *
     * **/
    public static int getMonthSpace(String firstTime ,String lastTime ){
        SimpleDateFormat sdf =new SimpleDateFormat("yyyy-MM-dd");
        Calendar c1 = Calendar.getInstance();
        Calendar c2 = Calendar.getInstance();
        try {
            c1.setTime(sdf.parse(lastTime));
            c2.setTime(sdf.parse(firstTime));
        } catch (ParseException e) {
            e.printStackTrace();
        }
        int result =(c1.get(Calendar.YEAR)-c2.get(Calendar.YEAR))*12+(c1.get(Calendar.MONTH)-c2.get(Calendar.MONTH));
        return result ==0 ? 1 : result;
    }

}
